Foam structure wound inserts for directional granulation

Abstract

A wound treatment system comprises a wound-treatment apparatus and a wound dressing coupled to the apparatus. The wound dressing includes a foam structure wound insert having pores with a greater cross-sectional area when viewed from a first direction and a smaller cross-sectional area when viewed from an orthogonal direction. Methods for making such wound inserts may include compressing foam structure material having pores with a substantially uniform cross-sectional area. Methods for treating a wound using a wound insert.

The invention claimed is: 
     
       1. A wound-treatment method comprising:
 positioning a wound insert on a wound of a patient, the wound insert comprising a single-layer foam structure having:
 a first surface having a first plurality of pores with a first average cross-sectional area; and 
 a second surface having a second plurality of pores with a second average cross-sectional area that is less than the first average cross-sectional area, wherein the first average cross-sectional area is perpendicular to the second average cross-sectional area; 
 
 orienting the wound insert such that the first surface is proximal a bottom surface of the wound; 
 coupling a drape to skin adjacent the wound such that the drape covers the wound insert and the wound, and forms a space between the drape and the wound; and 
 applying negative pressure to the wound through the wound insert; 
 wherein when negative pressure is applied to the wound insert, airflow through the first plurality of pores is greater than airflow through the second plurality of pores, and wherein the reduction of airflow through the second plurality of pores is configured to inhibit granulation of the wound adjacent to the second surface. 
 
     
     
       2. The method of  claim 1 , where applying negative pressure comprises activating a vacuum source that is coupled to the wound insert. 
     
     
       3. The method of  claim 1 , further comprising:
 delivering a fluid to the wound through the wound insert. 
 
     
     
       4. The method of  claim 3 , where delivering a fluid comprises activating a fluid source that is coupled to the wound insert. 
     
     
       5. A wound insert comprising:
 a single-layer foam structure having a first surface and a second surface; and 
 a plurality of first pores on the first surface, each of the first pores having a first cross-sectional area on the first surface; and 
 a plurality of second pores on the second surface, each of the second pores having a second cross-sectional area on the second surface, wherein the first cross-sectional area is perpendicular to the second cross-sectional area; 
 wherein the first cross-sectional area of substantially all of the first pores is greater than the second cross-sectional area of the second pores, and the first cross-sectional area comprises a diameter no less than 2 millimeters. 
 
     
     
       6. The wound insert of  claim 5 , wherein the second cross-sectional area has a minor axis less than or equal to about 0.5 millimeters. 
     
     
       7. The wound insert of  claim 5 , wherein the first surface is a granulating surface.